Technology / Rockets / Bulkhead: A wall between two areas - in rocketry usually between two tanks, instrumentation sections or between motor chamber and tank.
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Technology / Motors / D Flange: A special end shield with holes for through bolts in the flange and is primarily used for mounting the motor on gear boxes or bulkheads. Standardized for frames 143T through 445T. 'D' flanges are not MORE
Technology / Aviation / Bay: Any specific compartment in the body of the aircraft. It may also refer to a portion of a truss, or fuselage, between adjacent bulkheads, struts or frame positions. MORE